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11.
Searching online information resources using mobile devices is affected by small screens which can display only a fraction of ranked search results. In this paper we investigate whether the search effort can be reduced by means of a simple user feedback: for a screenful of search results the user is encouraged to indicate a single most relevant document. In our approach we exploit the fact that, for small display sizes and limited user actions, we can construct a user decision tree representing all possible outcomes of the user interaction with the system. Examining the trees we can compute an upper limit on relevance feedback performance. In this study we consider three standard feedback algorithms: Rocchio, Robertson/Sparck-Jones (RSJ) and a Bayesian algorithm. We evaluate them in conjunction with two strategies for presenting search results: a document ranking that attempts to maximize information gain from the user’s choices and the top-D ranked documents. Experimental results indicate that for RSJ feedback which involves an explicit feature selection policy, the greedy top-D display is more appropriate. For the other two algorithms, the exploratory display that maximizes information gain produces better results. We conducted a user study to compare the performance of the relevance feedback methods with real users and compare the results with the findings from the tree analysis. This comparison between the simulations and real user behaviour indicates that the Bayesian algorithm, coupled with the sampled display, is the most effective. Extended version of “Evaluating Relevance Feedback Algorithms for Searching on Small Displays, ” Vishwa Vinay, Ingemar J. Cox, Natasa Milic-Frayling, Ken Wood published in the proceedings of ECIR 2005, David E. Losada, Juan M. Fernández-Luna (Eds.), Springer 2005, ISBN 3-540-25295-9  相似文献   
12.
信息检索中的相关性研究   总被引:6,自引:1,他引:6  
成颖  孙建军 《情报学报》2004,23(6):689-696
本文系统地阐述了国外信息检索中的相关性研究 ,具体的论述按照三个阶段展开 ,分别是 195 8年之前的第一阶段 ,195 8— 1976年的第二阶段以及 1976年之后的第三阶段 ;其中每一阶段的阐述又被分为理论与实证两部分  相似文献   
13.
情报检索系统用户相关性判断的灰色聚类决策   总被引:2,自引:0,他引:2  
所谓灰色聚类决策,就是按多个不同的决策指标对决策对象进行综合评价,以确定决策对象是否满足给定的取舍原则。该方法可以用于对情报检索系统的检索结果进行相关性判断。参考文献4。  相似文献   
14.
This article proposes the incorporation of learning science into the programming and operation of public libraries. Learning science, a multidisciplinary field spanning cognitive science, psychology, neuroscience, economics, anthropology, and linguistics, has identified proven methods for enhancing learning at any age. The article highlights some of the tools and insights that are most relevant to libraries in their role as centers for informal learning.  相似文献   
15.
This study assesses the handwriting of isolated cursive letters in five-year-old children and the effect of a modification in visual feedback. Sixty-four children copied twelve cursive letters with an inking pen and a non-inking pen. Reducing visual feedback decreased the mean number of penlifts, and increased mean velocity and fluency. However, it increased the size of the letters (trajectory length) and reduced their quality. We suggest that processing visual feedback of the emerging visual trace may interrupt the fluency of the movement, while writing without seeing the trace may place greater emphasis on motor control and the use of somatosensory feedback. This study supplies reflection about sensory feedback and the moment when it should be provided in handwriting instruction. Practitioners should be aware that variation in the writing environment (surface, tools …) modifies sensory feedback and affects handwriting learning (gesture and outcome) in different manner.  相似文献   
16.
运用文献资料法、逻辑分析法和经验总结法,对足球运动员移动能力训练进行研究.指出,移动能力是足球技能的重要组成部分,与球员的比赛表现密切相关.在对移动方式特征和分类进行分析梳理的基础上,针对长期被忽视的发展感知能力和移动效果反馈两方面,提出足球移动能力训练的内容和重点,以及不同训练阶段的训练要点.认为,发展移动能力要符合力学原理、结合专项技术训练,最终实现训练能力向比赛能力的转化.  相似文献   
17.
The present study examined the effects of anticipated achievement feedback on students' semantic processing on the neural level, using event-related brain potentials (ERPs). Participants (N = 79) anticipated either self-referential or normative achievement feedback regarding an announced upcoming test. Additionally, their performance expectations (low vs. no expectations) were orthogonally manipulated. Subsequently, students' on-line semantic processing was assessed by measuring the N400 cloze effect, a component in the EEG signal of which the amplitude is associated with semantic processing. Within the low performance-expectation condition, no effect of anticipated feedback on semantic processing was found. Within the no-performance-expectation condition, participants anticipating self-referential feedback showed a more widely distributed N400 cloze effect than participants anticipating normative feedback. The results confirmed the hypothesis that the mere expectation of a particular type of feedback can affect students' semantic processes.  相似文献   
18.
The current study is to examine the interactional effects of writing conferences focusing on negotiated patterns of revi?sion in a college English writing class. Fifteen participants were required to w...  相似文献   
19.
Automated Writing Evaluation (AWE) program is designed to provide instant scores based on automated writing scor?ing engine along with diagnostic feedback. Five main AWE programs are introduced, four i...  相似文献   
20.
关联理论认为交际过程是一个明示-推理过程,但从听话人的角度来看,交际中的关联实际只是一个推理的过程。听话人的推理过程往往受到个人因素的影响,本文以莫言的长篇小说《蛙》为语料,分别从四个因素:先存经验的不同、对语境的不同评价、意向的动态变化性以及个体不同的凸显方法来分析汉语言语礼貌的理解机制。  相似文献   
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